Making producer gas



June 3, 1930..

Original Filed Aug. 10 1920 M, F. CHASE ET AL 1,761,384

MAKING PRODUCER GAS 2 Sheets-Sheet l Y FGURE l June's, 1930.- M. F. C ASE ET AL 1,761,384

MAKING PRODUCER GAS Original Filed Aug. 10, 1920 2 Sheets-Sheet 2 C- lolbapor m'm.

CO 552. ft

Hz I Hus Gas Prod uc er HzO- z lbs. 35.52

CO 35.x {+9 CO2 sis-2| fr? H1O "E 4-4 Oz. no.5: N:-- 55.92.

sum-

FI URE 2 Patented ,iunefi, i930 MARCH 1 CHASE, OF AltDSLEY-ON-THE-HUDSON, AND FREDERIC E. PIERCE ANDJO H N rut-m4 ice- SKOGMARK, OF NEW YORK, N. Y., ASSIGNORS TO THE, COS PROCESS COMPANY, INC, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK MAKING PRODUCER GAS Application filed August 10, 1920, Serial No. 402,718. Renewed March 29, 1928.

The object of our invention is to provide a practical and economic process of manufacturing producer gas of greater calorific power than hitherto produced as well as to provide the apparatus requisite for carrying 'on such process, and theinvention also has other incidental objects and advantages all of which will be made apparent inthe following description.

Briefly stated the invention contemplates the operation of. the gas producer in the usual way and with substantially the usual reactions except that in place of some or all of the air ordinarily used, a' special gaseous mixture is admitted to the combustion .zone, such mixture contalning less nitrogen and other inert gases, and more oxygen than air I is available for driving the blower or blowand thereby serving to make a producer gas with a low percentage of nitrogen and other diluents and therefore with a high content of heat units. {Ihe' invention further -contemplates the diversion-and-use of a small part of the rich gas thus produced for the manufacture of the said special mixture, which is done in a continuous'cycle and in such manner as to derive power as aby-. product of said manufacture, which power ers or otherfpu-rposes incident to operation ofthe process.

Figures 1 and 2' respectively illustrate the plan of the apparatus and the cycle of its operation.

In Fig. 1, we illustrate, the process diagrammatically. The gas producer (1) receives the coal or carbonaceous material to be gasified and may be assumed to be an ordinary type of producer. The gas passes to the assembly of necessary purification upparatus which is called the scrubber and marked (2) and, passing through which, the

- gas will becooled and tarry matters and other objectionable impurities removed. The

I larger part of the gas is thence passed by the valve 3 to the delivery pipe 3 leading to its place of storage or consumption. The.

and passed to a combustion device 5 where it is utilized to do work. Such device may be the burner of a boiler or furnace or an internal combustion engine or its equivalent and is here assumed to be an engine and to be used fordrivingthe blower 7 for maintaining the circulation of the gases. The producer gas delivered to it may be enriched, when-and as necessary, by admitting oxygen, or an oxygen-containing gaseous medium through the valve 4? from a source 4 and the combustion products of this device are drawn through a'gas cooler 6by the bloweror gas pump 7 and from the latter pass by pipe 9 to the prbducer, but in transit thereto they are enriched by a further amount of oxygen admitted through the valve 4 from the oxygen source 4, thereby, forming the special gasproducer operating mixture above re-' ferred to. A by-pass 10 from theaoutlet of the blower serves to return more or less of the products of combustion, with the oxygen gas medium added to them, to the combustion apparatus, according to the setting of its valve 10*, thereby providing a means for regulating the flow to the producer as well as the How to the device 5, or engine.

A-.boile r 8 furnishes and controls the amount a of steam necessary for the operation of the gas producer, and other usual appurtenances .to producer systems may be assumed to be marsh gas. (CH and other hydrocarbons as combustibles, with. carbon dioxide (CO and nitrogen (N as the principal diluents, the nitrogen carrying with it small percentages of argon and other inert gases derived drogen' (H with smaller quantities of from the air used in the process. The mixtureof air and steam forced into the bed of fuel in the producer brings about several chemical inter-reactions resulting in a gas generally analyzing about as follows,,for example: CO-*20%'to 25% H -8% to 12%: CH etc. 2% to 47%; (XL-4% to 8% with O and'N and other hydrocarbon gases, making up the balance to 100%. Such a gas will have a calorific value between 125 to 150 B. t. 11. per cubic foot. The large percentage of N and diluents, necessarily present in the producer gas, because of the air used in its production, and the ever, present CO limit the calorific power so that it rarely exceeds 150 B. t. u. per cubic foot.

In the operation of our system above outlined the producer reactions occur from the combination of the carboniferous material and steam with a gaseous mixture, constituted of the combustion products of the device 5 which are supplemented or enriched by the addition of oxygen as stated. Such a. mixture maypossibly contain some elements having a fuel value depending on the manner of operation of the said device and will of course contain CO: and some nitrogen but these diluent and substantially inert components will constitute a less percentage than the percentage of inert gases ordinarily entering the producer when it is operated by air. The proportion is under control by regulation of the amount of oxygen added or by regulation of the percentage of oxygen present in the source 4, the result being that the reactions are more efficiently conducted and the generated gas far richer in units than could otherwise be thecase. The oxygen addition may be derived from any suitable source, several inexpensive methods being known to the art and available for the purpose. It is of course unnecessary that it be pure, any oxygen-containing gaseous medium of fairly high'oxygen content being suitable.

The various valves shown, and others where necessary, and also the blower, which may be of variable speed, and its by-pass furnish the means whereby the gas producing operations are regulated and controlled. The blower or gas pump may obviously be located at anypoint in the system where it will maintain the gas flow as desired and accordlng tothe kmd ot system and apparatus in which the invention is used, and

moreover its functions may be performed by several blowers as desired.

In the operation of the plant, temperatures are taken and samples of the gases at the several stages of the process from time to time, and analyses of these samples are made.

The temperatures and analyses can be easily taken care of, if desired, by the well known automatic recording machines. The constituents of the gases at the several stages of the-process obviously determine the adjustments to be made and it will be noted that the cycle of operations a continuous process which can be controlled as a whole as well as in respect to its individual steps or stages.

Figure 2 is a simplified illustration of a typical gas cycle according to this invention.

heat

Carbon is charged into the gas producer at the rate of 10 lbs. per minute. This is gasified by 184.07 cu. ft. of gas mixture per minute forced into the producer together with 2 lbs. of steam per minute, this being 20 per cent of the weight of carbon charged. The total amount of gas produced is 412.21 cu. ft. per minute containing 332.11 cu. ft. (80.5%) of carbon monoxide, 44.18 cu. ft. (10.7%) of hydrogen and 35.92 cu. ft. (8.8%) of nitrogen. Such a gas has a theoretical heat value of about 310 B. t. u. per cubic foot according to the cycle illustrated and will of course be recognized as superior in calorific value to present day products. 90 per cent of it is available for commercial purposes and 10 per cent is recirculated and used in the process. The portion retained for circulation is mixed with the oxygen gas medium from the source 4, containing, for example, per cent, of,

oxygen. The amount of this medium required is 101.67 cu. ft. per min. containing 1.29.34 cu. ft. of oxygen and 32.33 cu. ft. of nitrogen and other inert diluents. All of this may be mixed with the recirculated portion and passed through the combustion apparatus or only a part of it, as circumstances may require. The. by-pass effects the necessary division if only a part is used,

the balance being added to the products of combustion. If a 10 per cent portion of the total gas product is mixedwith a part or all of such addition of oxygen gas medium and used in an internal combustion engine, as suming an efficiency of 30%, there would be developed about 83 engine horse power for blower-driving or other purposes. The heat ofthe exhaust of the engine or device 5 may also be used for heating the feed water to the boiler 8, in any suitable way, not illustrated. The products of the combustion in device 5 consists of 3321 cu. ft. perininute of carbon dioxide and 4.42 cu. ft. of water vapor mixed with the 3.59 cu. ft. of nitro' gen in the recirculated portion and the 32.33

.cu. ft. in oxygen gas mixture amounting together to 35.92 cu. ft., the excess oxygen amounting to 110.52 cu. ft. per minute, and the products of combustion with the uncombined balance of the added oxygen-containing medium amounting as previously stated to 184.07 cu. ft. per minute. Preferably the combustion products of the device or engine 5, will contain not over 55% N and at least 45% CO and after mixing with oxygen, not over 70% of N, or less than 15% CO; nor less than 10% It has been assumed in the case illustrated that 10% of the total gas product is used for circulation through the combustion device 5, but this amount may be from 5% to 35% (when corrected for temperature) without impairing the economies and depending upon the manner of utilization of the power derived from the tinuous and even working, as we have already explained, can be made under any given set of conditions and the process can be applied to obtain results surpassing any that have hitherto been possible.

Having thus described our process it will be seen that we have disclosed a continuous process for the manufacture of producer gas by circulating gases through a cycle of operations, with means for controlling and regulating the volume, temperatures and constituents thereof, which results in a gas product of high calorific value and which by contrOlling the percentage of the oxygencontaining additionmay be made of the greatest possible calorific value.

'l/Vhile we have described above the particular embodiment of our invention which we consider gives the most advantageous results, it should be understood that we do not mean to limit ourselves to that exact process or to the identical steps described nor to all of such steps, since obviously many changes may be made therein Without degas, mixing the remaining portion with oxygen, the gases being of predetermined volume and constituents at the mixing stage,

being not over 55% N and at least 45% CO and at such stage having added to them a predetermined amount of free oxygen or a medium with a higher'content of free oxygen than air and after such mixing operation containing not over of N nor less than 15/0 CO nor less thanv 10% O and using said mixture in making producer gas.

3. In the manufacture of producer gas, a continuous process of producing gas of greater calorific value than 150 B. t. u. per

cubic foot, which consists in continuously passing a gaseous mixture through a gas producer, diverting a substantiallyconstant major portion of the produced gas to a place of storage or use, circulating the remainder through a path leading back to and through the gas producer and. a combustion unit, thereby developing power and products of combustion, introducing into said path of circulation a substantially constant amount of free oxygen or gaseous medium having a higher free oxygen content than air, and utilizing said developed products of combustion in the operation of said gas producer.

In testimony whereof we have signed this specification.

' MARCH F. CHASE.

FREDERIC E. PIERCE. JOHN SKOGMARK.

parting from the spirit of our invention, the

principle of which has now been explained.

Claims- 1. In the manufacture 'of producer gas, a continuous process for the production of gas ofgreater calorific power than 150 B. t. u. per cubic foot by continuously passing gases through a cycle of operations con-- sisting of gas producing, diverting a portion of the gas for storage or use, the remaindcr being of predetermined volume and constituents, and when corrected for temperature being between 5% and 35% of the volume of gas leaving the gas producer and containing not over 55% N and not less than 45% of CO, mixing the same in such volume and of such constituents, with gas producing, diverting a portion of the 

